JavaZone, one of the biggest European Java conferences, is now over. I was able to take part in it using my conference allowance at Kahoot!. Although the ticket is fairly expensive (around 8 500 NOK for a late-bird ticket), in my opinion, it was a very good conference.

Let’s start with a couple of things that I really liked about this conference or which differed from my previous experiences:

Overflow zone

The conference took place in Oslo Spektrum, a big venue right next to Oslo central railway station that hosts mostly concerts. Some of the seats on the balcony were converted into a zone where one could watch streams from all 7 rooms and listen to the sound on a headset. You could choose which talk to listen to by changing the channel on an IR device. That meant that it was possible to peek at other talks and if the one that you were listening to at the beginning felt not really suited for you, you could quickly change without causing any commotion in the rooms. It was a very popular zone, and, to be honest, I watched all the talks from there. It still differed a bit from watching the conference online – you still could catch the speaker to ask some questions after all. I’d love to see it at more conferences.

The food

There were (I think) 7 restaurants from all over Oslo that set up makeshift kitchens in the main hall. Each of them was sponsored by one of the companies that had booths next to the restaurant and a huge banner behind.

The food was amazing and included in the conference ticket.

This, for instance, is a lamb wrap in a lefse – Norwegian potato bread.

To add to it, there were coffee stands all over the hall and on the hallways. You could also get some soft drinks, ice cream from two different providers (one with an optional bacon topping) and the Norwegian police booth was living up to the stereotype, serving donuts.

A different community

It felt like the JVM community that assembled at JavaZone, compared to Confitura that I visited a few months ago, was a bit more experienced and definitely more diverse. That’s not that surprising given that it’s in Norway. The speakers were also coming from all over the world, though of course, the most were from Western Europe. While there were talks in Norwegian, the majority of the talks were conducted in English.

A different approach of the companies

Of course, they were recruiting there as well. Compared to Confitura though, the stands were not filled with multiple jobs postings and the swag was less visible too. Instead, many companies organized something for the developers to play with. There was a toy railway, a pretty huge RC car track, pinball machine, several retro consoles, quite a lot of lotteries and one company was hosting kahoots, giving out money (1000 NOK for the winner on each break, 10 000 NOK for the final kahoot of the day). There was also a so-called IT-championship in table tennis.

So was it worth it?

I would have a hard time paying for the conference by myself, but if you have a conference budget that can cover for this one or enough money to fly to Oslo, pay for the conference and spend 2 days in Norway – sure!

Use technologies that you’re familiar with if you want to achieve results

Learn technologies at work if you can, not at home…

Unless your project’s purpose is to learn a new technology. Then pick one and do the rest in familiar stuff or assume it won’t get finished and it’s likely not to go far enough for you to learn anything

9 out of 10 startups with fresh ideas fail. 5 out of 10 startups that copy others don’t

It’s about time – Christin Gorman

Hilarious introduction into all the potential problems related to the absurd, legacy system that we all deal with (which is our global date/time system)

Which classes should be used in Java to store date/time and how to deal with storing date/time in DBs (namely PostgreSQL and MS SQL Server)

Storing in UTC is almost always a good idea

What might be hard – comparing results (i.e. stores sale volumes) by day between various timezones

Java Modularity: the Year After – Sander Mak

Over 80% of developers are still using Java <= 8 on production

Only 20% of the developers that use JDK 9+ are using modules at all

Adoption of JDK9 is much smaller than JDK8 was at this point after its release

Mostly because it contains changes that aren’t so useful to developers’ daily work

From new packages pushed to Maven Central during 3 weeks in August ‘18, only 1% was using modules and 9% had at least Automatic-Module-Name to reserve their module name. That means 10% packages were module-aware at all

The author suggests that JDK11 is more likely to gain traction because of the LTS

GraphQL – The Next API Language – Niek Palm

Introduction to GraphQL and how to use it with Spring Boot

Mostly describing how features like filter work and how to mutate objects

Native Agile Psychology of Teams and Individuals – Valerie Andrianova

I mostly switched on and off this talk for some time, so I might have the full notion here

It sounded mostly like a description how JetBrains are doing their development and keep their devs happy